
const cloud = require('wx-server-sdk')
exports.main = (event, context) => {
  let { userInfo, a, b } = event
  let { OPENID, APPID } = cloud.getWXContext() // 这里获取到的 openId 和 appId 是可信的
  let sum = a * b

  return {
    OPENID,
    APPID,
    sum
  }
}